| 摘要 |
PURPOSE:To enhance the ratio of a recorded area to the area of an optical disk and to accomplish the large capacity of the disk by constituting both a land surface and a groove surface as the recorded area in the optical disk where the land surface and the groove surface having different heights are alternately arranged in a radial direction. CONSTITUTION:The dimensions of the respective widths of the land surface 2 and the groove surface 3 are the same and the surfaces 2 and 3 are formed in the dimension where recording is possible so as to constitute both of them as the recorded area. By positioning an optical pickup at a position opposed to the land surface 2, a pit 5 is formed to perform recording and also readout is performed with reflected light from the pit 5. Next, by positioning the optical pickup at a position opposed to the groove surface 3, the recording and readout are performed in the same way. At such a time, an inclined surface 4 serves as a guard. Thus, the ratio of the recorded area to the area of the disk is enhanced and the large capacity of the disk is accomplished by performing recording on both surfaces 2 and 3. |
